The long-distance transport of visible light through a building can use large mirror-lined ducts, or smaller solid fibers which exploit total internal reflection. Mirror-lined ducts include advantages of large cross-sectional area and large numerical aperture (enabling larger fluxes with less concentration), a robust and clear propagation medium (that is, air) that leads to both lower attenuation and longer lifetimes, and a potentially lower weight per unit of light flux transported. Regardless of the technique used to transport light effectively, a practical and efficient daylight collector that can also concentrate the collected light, and a technique to accurately align the concentrator is needed.